When the gates of Hell appear in Karakura Town and strange spirits called Unforgiven (Togabito) escape, Rukia Kuchiki and Renji Abarai are sent to investigate. Ichigo Kurosaki's family is targeted by the Unforgiven, who are led by Shuren, and Ichigo's younger sister Yuzu Kurosaki is abducted. An Unforgiven named Kokutō saves Karin Kurosaki from being abducted as well, and convinces Ichigo to accompany him and the Soul Reapers to Hell to save her. On the journey to Hell, Ichigo's Hollow mask begins to spontaneously manifest and Kokutō warns him to avoid using it lest he lose control and hollowfy entirely. Ichigo, Rukia, Renji, Ishida, and Kokutō battle Shuren and the other Unforgiven, and it becomes apparent that Shuren plans to use Ichigo's hollow powers to escape Hell. After Shuren and the other Unforgiven are defeated, Kokutō betrays Ichigo and reveals he was the true leader of the Unforgiven and the one behind Yuzu's kidnapping. Kokutō kills Yuzu and an enraged Ichigo hollowfies, blasting Kokutō with his Cero, destroying most of the chains binding Kokutō to Hell and burning through the gates of Hell. Renji breaks Ichigo's Hollow mask and grabs Yuzu's corpse while they are extracted by Soul Society, but Rukia, Renji, and Ishida are captured. When Yuzu spontaneously revives, Ichigo, despite being forbidden to do so by Soul Society, returns to Hell to rescue his friends and confronts Kokutō, who killed Renji and Ishida and was torturing Rukia. Resisting hollowfication, Ichigo undergoes a transformation after being given power by the Hell guardians, becoming covered in bones, and defeats Kokutō, bringing his friends back to life and escaping Hell as the gates repair themselves and vanish.